Grinding wheel for soft materials



Dec. 12, 1939. A. MONTAG-NE GRINDING WHEEL FOR SOFT MATERIALS File d March 7, 1938 I Patented Dec. 12, 1939 UNITED STATES- PATENT OFFICE Anton Montagn, Dusseldorf-Gutenberg, Germany Application March 7, 1938, Serial No. 194,333 In Germany October 15, 1935 6 Claims.

As is known, hard grinding wheels of emery or the like with mineral or ceramic binding agents are employed for grinding soft materials, As such wheels, when dry grinding, easily become clogged with the ground off material and become hot, grinding wheels have already been proposed with metal elements having cutting edges and arranged on their periphery. However, the known grinding bodies are composed of a large number of elements the fixing of which on the periphery of the wheel requires a large number of fixing means which make the manufacture of the grinding wheels complicated and expensive.

The present invention relates to a grinding wheel for soft materials, such as leather, artificial resin, soft metal and similar materials, composed of a wheel as carrier and of a metal body with cutting edges, in which the chips cannot lodge and the cutting edges cannot become hot. The characteristic feature of the invention consists in that the grinding body proper consists of a single metal part in the form of a helical spring which is exchangeably fixed on the periphery or on the surface of the wheel perpendicular to the axis thereof, and presents to the workpiece grinding portions arranged like radial arms and resilient in the direction of rotation and feed. As compared with theknown grinding wheels with separate grinding bodies a grinding wheel of this type represents a considerable simplification owing to the elimination of complicated parts and fixing means.

Several embodiments of theinvention are illustrated in the accompanying drawing in which- Fig. 1 shows in part elevation a grinding wheel with grinding body arranged on its periphery,

Fig. 2 shows in a similar view a grinding body arranged in a plane perpendicular to the axis of the wheel,- 7

Fig. 3 shows a grinding body of rectangular cross-section,

Fig. 4 shows a grinding body of oval crosssection,

Fig. 5 shows a grinding body of oval cross-section on the side of a carrier,

Fig. 6 is a cross-section through a fiat wound grinding body,

Fig. 7 shows in part cross-section a grinding wheel with built-up carrier and grinding body of triangular cross-section,

Fig. 8 shows a grinding body wire of trapezoidal cross-section,

Fig. 9 shows a grinding body wire of triangular cross section,

Fig. 10 shows a grinding body wire of segmentshaped cross-section,

Fig. 11 shows a grinding body' wire of trapezium cross-section and narrow cutting edge,

Fig. 12 shows a grinding body wire of rhombic 5 cross-section.

The grinding body I is formed by a single endless wire of triangular, quadrant-shaped, rhombic or other cross-section wound in an oval, rectangular, triangular, circular or other 10 shape and removably fixed on the periphery or rim of a flat disc 2. The outer edges of the grinding body 1 form cutting edges and are spaced at a short distance so that the grinding body can be used in both directions of rotation. The grind- 1 ing body I is fixed on a carrier 2 or 2a made in one part or in two parts by means of a oneor two-part clamping ring 3, a strap 4, a clamping bar 4a or the like and accommodated. in an annular groove 5 in the periphery or in the 20 side face of the disc 2 or 2a respectively or in transverse grooves 6. The two parts of the carrier 2a are pressed together by clamping means,

' such as screws, and clamp with the cheeks of its grooves 5, especially in the case of the triangular- 25 1y wound grinding body I shown in Fig. 7 of the drawing together with the two-part clamping ring 3 having a cross-sectional shape conforming with that of the grinding body, two arms of the grinding body. When using grooves 6 which can 80 be employed in connection with an annular groove 5, the groove cheeks I serve at the same time as spacers between the individual coils of the grinding body I. Fixing means 3, 4, 4a with transverse ribs 8 may be employed instead of 85 transverse grooves 6.

The cutting edges of the grinding body I act in rapid succession on the workpiece, and, owing to the rung-like arrangement of the grinding parts the air brushes against the grinding body and 40 exerts a good cooling eifect. In the case of surface grinding wheels the rungs of the grinding body are preferably so arranged that they engage the workpiece with backed ofi cutting edge. The depth of out can likewise be regulated by the position of the cutting edges. To avoid wide chips the cutting edges are provided with chip breakers 9 which are formed by grooves inclined to the direction of cut.- When the actual cutting edges become blunt the special construction 5 of the coils enables the grinding body to be turned to bring the other portions of the coils into cutting position.

The grinding body I is mostly made of steel but bronze or the like can also be used.

I claim:

1. A grinding wheel for soft materials, comprising in combination a carrier disc, a grinding body formed of an endless coil of helically wound wire of such cross-sectional shape that the individual windings of the coil have cutting edges on both sides and consequently out in both directions of rotation and the cross-sectional shape of the helically wound wire coil is such that at least two cutting sections are formed on each side of each winding, said sections adapted to be alternately brought into operative position by turning said coil about its central axis, and a clamping ring securing said coil on said body.

2. A grinding wheel as specified in claim 1, in which the rungs of the metal body are of tin-- angular cross-section.

3. A grinding wheel as specified in claim 1, in which the rungs of the metal body are or quadrantal cross-section.

4. A grinding wheel as specified in claim 1, in which the rungs of the metal body are of rhombic cross-section.

5. A grinding wheel as specified in claim 1, in which the disc has uniformly spaced transverse grooves accommodating said metal body and maintaining the cutting edges at uniform distances apart.

6. A grinding wheel as specified in claim 1. in which the disc has uniformly spaced transverse ribs engaging said metal body and maintaining the cutting edges at uniform distances apart.

ANTON MONTAGNE. 

